A BBC international opinion poll suggests there is widespread disquiet about the United States' role in Iraq and its other foreign policy priorities. The BBC's Jonathan Marcus analyses the results.

The US knows how to use hard power to back up its interests

The Bush administration's toppling of Saddam Hussein has had several profound and unintended consequences.

One has been the way in which the destruction of both the Taleban regime in Afghanistan, and of Iraq's military machine, have opened the way for the rise of Iran as a major regional player.

Another crucial but less tangible problem - as this opinion poll commissioned by the BBC World Service indicates - is that the US's image around the world is being seriously damaged by the chaos in Iraq.

And if that was not bad enough, it suggests that America's image problems are only getting worse.

The global image of the US has significantly deteriorated over the past 12 months, as the chaos in Iraq has deepened. And in 18 of the countries that were involved in previous polls, the slide in America's standing has steepened.

Anti-Americanism rising

Overall, this new opinion poll sampled the views of 26,000 people in 25 countries.

Three in every four of those questioned disapproved of how the US government was dealing with the crisis in Iraq.

The poll did not just deal with Iraq. It also asked questions about the US handling of Guantanamo detainees; the Israel-Hezbollah war; Iran's nuclear programme; global warming; and North Korea's nuclear programme.

In every case, a majority of those questioned disapproved of America's handling of the issue concerned.

This poll underscores conclusions drawn from several other surveys - that anti-Americanism is on the rise, and the more the US flexes its hard power - the more it deploys troops abroad or talks tough diplomatically - the more it seems to weaken its ability to influence the world.

But then there was still the Cold War to keep America's allies on-side.

What is striking in this survey is how negatively the US is seen across a range of diverse countries. Indeed the same policies are, in many cases, even unpopular in the US itself.

This, then, raises an obvious question. Is it simply the Bush administration's foreign policy or the whole image of America that is unpopular?

Comparable surveys suggest that there is still strong support around the world for the values enshrined in US society. But it looks as though America itself is seen to be living up to those values less and less.

As a result, America's soft power - its ability to influence people in other countries by the force of example and by the perceived legitimacy of its policies - is weakening.

And in a turbulent, globalising world, where the US - rightly or wrongly - is associated by many with the disruptive effects of globalisation, soft power matters more than ever. It is a resource that once squandered is very difficult to build-up again.

Complex issues

At root is the problem of legitimacy.

Iraq may have dented the utility of America's military machine. But the US remains the world's only superpower in an international system that shows few of the familiar landmarks we have come to associate with the past 50-or-so years of international diplomacy.

Opinion polls, by their very nature, are a snap-shot. They ask very particular questions and they need to be interpreted with caution.

Asking, as this survey does, about the participants' opinion of the US government's handling of, say, Iran's nuclear programme, provokes strong levels of disapproval.

But what does this really mean? Is there any constituency at all for getting tough with Iran? How far is Iran's nuclear programme perceived as being a problem at all?

Other opinion polls, asking different questions, suggest that ordinary people in many of America's allies are indeed worried by the suggestion that Iran might acquire nuclear weapons.

It is the Bush administration's handling of the issue that is reflected in this BBC poll; not the policy options themselves. These are complex. They depend upon often unavailable intelligence and uncertain assessments of what the Iranian authorities are really about.

Opinion polls are not terribly useful then in charting specific policy options.

But they do capture a mood and that mood should worry anyone in policy-making circles in Washington DC.

The US undoubtedly has an "image-problem", and there are worrying signs that this is having an impact upon the administration's ability to get the policy outcomes that it wants.

One of the wisest writers on these issues is Joseph S Nye, now Dean of the John F Kennedy School of Government at Harvard University. He is in many ways "Mr Soft Power", having written and theorised about the phenomenon for many years.

He has long-argued that Americans need to better understand how their policies appear to others.

"To communicate effectively," he has written, "Americans must first learn to listen."

This opinion poll, then, represents a powerful argument for those seeking to make the case that Washington should listen more and try to win over its friends as much by persuasion and force of example as by firm actions and tough rhetoric.